[meteorite-list] About the meteorite of Prambachkirchen, in GERMAN!
http://www.nachrichten.at/magazin/erforscht/486940? PHPSESSID=2bb12ad4e467bfc383fc435f07f7ef4e Peter __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Is that beer on your tie? (yes, on-topic)
Don't know if they are serious about the mention of meteorites or not, but if so some of us might want to take them up on the offer. http://www.the-scientist.com/news/display/25122/;jsessionid=448543B377A09AAA4E7FF120AC9CB3BF Is that beer on your tie? A molecular biophysicist helps fund his lab with lush microphotos that decorate neckties, calendars and greeting cards [Published 20th October 2006 03:41 PM GMT] In Michael Davidson's photographs, a Tylenol pill looks like a tie-dyed explosion, a drop of Pina Colada appears to be an array of peacock feathers, and an Intel microprocessor resembles a futuristic urban map. To achieve these effects, he gets close to his subjects -- really close. For the past 35 years, the molecular biophysicist, who heads up the Microscopy Office at Florida State University's National High Magnetic Field Laboratory, has captured the intricate universes under his microscope slides and developed them into vivid works of abstract art. The lush images have been reproduced on neckties, calendars, sportswear, and greeting cards. Though he never studied art or photography, Davidson has landed an astonishing 1,500 magazine covers. And his lab's artistic arm, Molecular Expressions, has created nearly 750,000 images, including microphotos of DNA, vitamins, pharmaceuticals and beer, to name a few. (The lab is always looking for original samples. Should you have any dinosaur bones or meteorites lying around and be willing to make a short-term loan, they'll deliver free color microprints of the objects in return.) The team is well versed in technologies ranging from confocal microscopy to live-cell imaging, but turning science into art presents a new set of technical challenges. To create his striking images, Davidson had to find ways to bridge the gap between what he saw through his microscope and what the camera lens saw. Because the eye detects more fluctuations along the color spectrum, the challenge has been creating specimens that work as well for the camera as they do for the human eye. For starters, the molecules have to be in crystalline form, so that they will generate the contour-revealing colors of polarized light. In a touch of poetic justice, it's the defects that reveal the most striking designs and patterns. A flawless diamond would just look like a mirror under the microscope, Davidson said. Preparing the specimens can take weeks or months. Davidson's expansive collection of microimages of beer, for example, was particularly grueling to put together. A lot of beers are pretty close to one another, chemically speaking, he explained. Only a few motifs are different, yet we had to assign a distinct pattern to each brand. Once the specimen is ready, an understanding of composition is essential to good microphotography, said Davidson, who now uses digital instruments to snap the shots. The way a photograph is framed has a dramatic impact, he said, noting that that's what he most impresses upon his lab employees, now that he has stepped into a less hands-on role in the microphotography enterprise. Rather than do it myself, I critique the others. I'm trying to generate baby Picasso microphotographers! When not honing their aesthetic sense, the lab members are developing microscopic techniques. In September, Davidson and colleagues published a report in Science on photo-activation location microscopy, which enables researchers to see high-resolution single molecules in biological structures. Despite the success of his microphotography venture, Davidson said he still sees the art as primarily a way to fund his science habit. It was a matter of survival at first; we had been working for funding from NIH for so long. And then we found we could sell these photos and make more money than I ever imagined. The neckties alone brought in $1.5 million in the 1990s, with the beer and cocktail images being the hottest sellers. Much of the profits were reinvested in lab equipment and used to launch its extensive educational websites for students of all levels of microscopy. Davidson's broader mission is to use his compelling images to generate interest in science. Someone's not likely to read a paragraph on vitamin D, but if they see a beautiful picture of it next to the [paragraph], they are more likely to read it. Still, some of the most beautiful things in science, you can't slap up as a photograph, Davidson said. Take line DNA replication. It's so complex. The multiple mechanisms are just incredible. Far more beautiful than any photo I have taken. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
RE: [meteorite-list] Re: Ad New Lunar Seymchan Bessey Specks
Hi Mike, list - Just when Bessey Specks were finally out of my conciousness, along comes another cut lunar - Okay. How about cuttings as in cuttings from NWA999 Lunar/Martian meteorite preparation by as an alternative to Bessey Specks? Put that on the tag alongside your picture of the Moon or Mars, and that way both the rock and the preparer get credit, if the child ever reads it carefully as he grows up. lunar cuttings martian cuttings cuttings Now sell at Air Space, Houston, Kennedy in those child proof little acrylic bullion holders Anne showed. arghh - enough: a neologism and perhaps a new market. Maybe the IMCA could organize this good hunting, Ed Man and Impact in the Americas --- MARK BOSTICK [EMAIL PROTECTED] wrote: That 146.4 gram Seymchan piece is just awesome Mike. http://jensenmeteorites.com/Seymchan.htm Clear Skies, Mark Bostick www.meteoritearticles.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Tuscon show dates
test Steve Arnold,Chicago,USA!! BIG Steve's Meteorites,1999!! __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] (no subject)
test Steve Arnold,Chicago,USA!! BIG Steve's Meteorites,1999!! __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] new email address
Hi list.I have a new email address.It is [EMAIL PROTECTED] update your records.Thanks and have a great day. steve arnold,chicago Steve Arnold,Chicago,USA!! BIG Steve's Meteorites,1999!! __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] email to the list from Phil Mani
Dear List, Phil was having difficulties getting his email to post to the list so I am forwarding it for him. From: mailto:[EMAIL PROTECTED]Philip mani To: mailto:Meteorite-list@meteoritecentral.comMeteorite-list@meteoritecentral.com Sent: Saturday, October 21, 2006 9:13 AM Subject: Brenham Project This letter is my first post to the Meteorite List after being a long-time reader. I am the fortunate beneficiary of much recognition from so many of you related to my Brenham Project with Steve Arnold. Thank you for your kind words and encouragements. With this posting, I wanted to publicly recognize certain individuals who are the main contributors, in my opinion, to our most recent expedition and without whose efforts and creativity the wonderful story written by Associated Press would not have been possible. It was last July when I began conversations with Carolyn Sumners, Director of Astronomy of the Houston Museum of Natural Science. I offered HMNS an opportunity to join Steve and I in Kansas on a meteorite search and recovery project. Mrs. Sumners was excited about the opportunity and asked me what specifically HMNS could contribute as far as unanswered questions about the find. I told her we questioned the timing/age-date assigned to the fall and we wished to try to pin-down its timing. We discussed several methods for age-dating and left her and her experts to further discuss and implement the methods for age-dating. A second question is the direction of the meteorite fall, specifically, its bearing and descent angle. This question is more complex and we felt we needed to gather as much survey information as possible without disturbing the meteorites and the soil around them. At this point, Mrs. Sumners contacted Dr. Essam Heggy with the Lunar Planetary Institute regarding his ground penetrating radar work. I informed Steve and he said he would do his best for the museum. I remained convinced he could find another meteorite. After all details with the HMNS, LPI, and our landowners were worked out, I contacted our good friend, Darryl Pitt, to assist with all facets for release of information to the public regarding this expedition. You all know our results. Steve was able to pull the golden rabbit out of the hat. My sincere appreciation and congratulations to him once again and, if you have seen the strewnfield you understand why. He tells me he feels his ability to do so again from this point on will be less and less. Therefore, our search and recovery efforts for Brenham meteorites is beginning to wind-up. Carolyn Sumners' group from HMNS included astronomers, geologists, paleontologists and archeologists with long and storied excavation and recovery experiences. It was a joy and a treat to be an observer of their efforts. I am excited for them and their unique meteorite recovery. Good going. Dr. Heggy, with LPI, was faced with a substantial change of conditions from those he originally anticipated in the field. Southwest Kansas had received quite a bit of rain and in the last three days, we were in constant heavy drizzle, blown sideways by 20-plus mile an hour winds. If not for the excitement of the project and all involved, it would have been miserable to be in such conditions for the 12 or more hours per day. Dr. Heggy adapted his equipment and techniques and continued to proceed as diligently as the rest of us without becoming discouraged. His efforts too were rewarded. Finally, but certainly not least, Darryl Pitt single-handedly prepared the initial press release and then he, along with the brilliant efforts of a colleague of his in New York, facilitated the amazing Associated Press story by Roxana Hegeman. Darryl worked closely with Roxana a day or two before Monday's final excavation of the museum's 154-pound pallasite and she was very well prepared for what to expect on the final day. It was only yesterday evening I learned that Roxana's story has enjoyed the widest world-wide distribution of any story ever pertaining to meteorites (with the exception of the announcement of ALH84001). Certainly amazing. I am grateful to be a part of the Brenham Project. I have learned much more than I ever anticipated being a meteorite collector. This particular chapter of our project was such a treat to watch unfold. I am reminded of Greg's words to the List that this is an awesome story where meteorite hunters, collectors and scientists can join to work together closely in the field using new equipment to make a wonderful meteorite recovery. I am blessed to have participated. Congratulations to Carolyn Sumners and her HMNS team for their thoughtful work and the additional, continuing work to come both in age-dating the fall and hopefully determining the fall direction and angle. Great-going Dr. Heggy for your successful use and application of the GPR. Hats-off to Darryl for facilitating the
[meteorite-list] Chondrule formation mechanism
Hi all - I think I would be right in saying that the usual mechanism proposed for chondrule formation is precipitation at low temperatures over time. But I am wondering: could chondrule formation be linked to the release of pressure? Could it be like a soda-pop, where when you take the cap off the CO2 becomes bubbles? Could chondules be mineral bubbles which formed when pressure was released on an immiscible suspension? It is often stated that there are no stupid questions, and I hope I have not provided an example to the contrary with this one. good hunting, Ed __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chondrule formation mechanism
On Sat, 21 Oct 2006 10:12:56 -0700 (PDT), you wrote: I think I would be right in saying that the usual mechanism proposed for chondrule formation is precipitation at low temperatures over time. No, actually it isn't. Chondrules are usually proposed to be products of rapid melting. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Portales Valley Q
Does anyone on the list know the current status of classification for Portales Valley? When it first fell, I believe it was merely classified as (H6), which I thought was insulting to one's logic. Then, I heard the classification had been changed (about time). However, I recently saw a Michael Cottingham card that read, (H7)? That seemed to me to be, indeed, odd. So, does anyone KNOW? Also, is there a DIFFERENT classification for the low metal vs high metal forms - or did the new classification address that? I am sure many list members would be interested to know. Thanks, Michael __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Portales Valley Q
Hello Michael and List, I don't have a final, definitive answer to your question. It is one that I, too, have been seeking an answer to for a long time. Here is a link to a fairly recent article that raises some good points: http://www.psrd.hawaii.edu/Sept05/PortalesValley.html Robert Woolard __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Portales Valley Q
Michael, This was the subject on the list just a year ago. I had expressed my favor of the journal article by A. Ruzicka et al. (2005), which referred to PV by a new term -- H-chondrite, metallic-melt breccia. Jeff Grossman posted the following in reply, which actually does seem like a completely logical classification based on the petrogenesis proposed in the above paper: -- Obviously there is disagreement among scientists on what to call PV. I personally see no reason to call it type 7, a primitive achondrite, an achondrite OR to coin a new term. If I take the conclusions of the Ruzicka study as a given, that you had H6 material near its peak metamorphic temperature, which additional shock heating and mobilization of metal-rich melt, then I see no reason not call it an H chondrite impact melt breccia in which the clasts are dominantly type 6. jeff - David __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] nearly nailed part three
Hi listees A fellow member was asking me if I recalled the name of a meteorite fall where a guy got mud splattered on him... My few remaining pieces of grey matter remind me that ENSISHEIM fits into this category but are list members aware of any other falls with similar circumstances - please post names of same to the list or message me Cheers __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] AD: EBAY NWA CLEARING OUT SALE
I have been pretty quite meteorite wise lately and didnt feel like updating my website for sold items so I have listed a couple hundred meteorites on ebay. These are mostly items that I have offered in the past but in an effort to clear out old stock, get ready for new meteorites next month, and to raise money for munich I have significantly reduced prices on everything - large proportions of my current ebay listings are under 10 cents a gram. See my ebay id AMUNRE or click here: http://stores.ebay.com/AMUNRE-COLLECTIBLES-AND-GEMSTONES_Meteorites_W0QQcolZ4QQdirZ1QQfsubZ4QQftidZ2QQtZkm Or if its to long this should work also: http://tinyurl.com/y5myap Sincerely DEAN BESSEY http://www.meteoriteshop.com __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] BESSEY SPECK INFORMATION NOW ON EBAY
In light of the recent discussion on this list about Bessey Specks and in the interest of new list members who were not around a few years ago when bessey specks came into existance I have listed this ebay auction to explain how it all started (And your chance to get your very own Bessey Speck). See my ebay auction #190043654452 Or click here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemcategory=3239item=190043654452 Sincerely DEAN BESSEY http://www.meteoriteshop.com __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Polandmet auctions ending OT AD
Hi again. 15 auctions ending in 24 hours including CV3 CV3-anomalous CR2 ODIO L6 IMB L3.1 http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemrd=1item=110044409830 This piece make me realy crazy. I have cut some ordinary meteorite fragments. I could expect anything special in this low quality material except rust, missing iron and dark matrix. But then a big surprize. One of my most lucky cuts I have ever made. I have cut this specimen just perfect into center of a large chondrule. Im not 100% sure , but this one looks like extra large 10x8 mm chondrule. Let me know what is Your opinion about this object. Visit my eBay shop http://stores.ebay.com/PolandMET-Store -[ MARCIN CIMALA ]-[ I.M.C.A.#3667 ]- http://www.Meteoryt.net [EMAIL PROTECTED] http://www.PolandMET.com [EMAIL PROTECTED] http://www.Gao-Guenie.com GSM +48(607)535 195 [ Member of Polish Meteoritical Society ] __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chondrule formation mechanism
Hi Darren - Thanks - much has been lost in the stroke. I also seem to remember a long slow cooling involved in chondrule formation - I am thinking that effervescence following a sudden release of pressure might be a better process description - good hunting, Ed --- Darren Garrison [EMAIL PROTECTED] wrote: On Sat, 21 Oct 2006 10:12:56 -0700 (PDT), you wrote: I think I would be right in saying that the usual mechanism proposed for chondrule formation is precipitation at low temperatures over time. No, actually it isn't. Chondrules are usually proposed to be products of rapid melting. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: Re: [meteorite-list] Chondrule formation mechanism
On Sat, 21 Oct 2006 14:58:23 -0700 (PDT), you wrote: Hi Darren - Thanks - much has been lost in the stroke. I also seem to remember a long slow cooling involved in chondrule formation - Googling chondrule formation comes up with lots of stuff, much of it pretty densly technical. Here's one interesting tidbit (unfortunately you have to buy the whole article to read it): http://www.aspbooks.org/custom/publications/paper/index.phtml?paper_id=2447 Chondrule textures depend on the extent of melting of the chondrule precursor material when cooling starts. If viable nuclei remain in the melt, crystallization begins immediately, producing crystals with shapes that approach equilibrium. If not, crystallization does not occur until the melt is supersaturated, resulting in more rapid growth rates and the formation of skeletal or dendritic crystals. A chondrule texture thus indicates whether nuclei were destroyed, which implies a melting temperature above the liquidus temperature for its particular composition. The presence or absence of skeletal or dendritic crystals in chondrules can be used to constrain their peak temperatures, which range from 1400-1850°C. Heating times of less than a second result in aggregates of starting materials coated with glass, resembling agglutinates rather than objects with typical chondrule textures, suggesting that heating times are longer. Chondrule textures can be duplicated with a very wide range of cooling rates, but if olivine zoning is to be matched the cooling rate should be within the range 10- 1000°C/hr. The size of overgrowths on relict grains cannot be used to infer cooling rates. Chondrules melted in a canonical nebular gas lose sulfur and alkalis in minutes, while iron loss from the silicate melt continues over many hours. Mass loss and isotopic fractionation can be suppressed if the partial pressures of the species of interest are high enough in the ambient gas. Chondrule bulk and mineral composition arrays can be reproduced to a large extent by evaporation. However, condensation of SiO into the melt can simulate the zonation in some chondrules, with pyroxene and a silica polymorph near the rims. The partial equilibration of chondrule melt with noncanonical nebular gas would require heating for time periods of hours. I am thinking that effervescence following a sudden release of pressure might be a better process description - Hm. Effervescence following a sudden release of pressure makes me think more of a can of Coke. :-) __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Permian-Triassic Mass Extinction Cause: 'SickEarth'
Hi, All,
Ah, press-release-science! The part of such
announcements that is annoying is that there is
no room in a press release for evidence, unless
it's one piece of new-discovery evidence. None
of that here. It's a theory...
So, as I read the (by now) many press pieces
on Sick Earth Syndrome. I assume that there
must a good record of long-term variations and
declines in Permian oxygen levels. That's certainly
what the articles imply.
I went a-Googling to find such a record, and --
guess what? -- there isn't one. The Permian was
an oxygen rich period mostly. There IS a record of
an event covering less than a half million years
which shows a thin layer with a sudden and dramatic
drop in oxygen accompanied by a dramatic marine
extinction, then a thicker layer showing a partial
recovery to still-low oxygen levels accompanied
by continuing extinction at a lesser rate, followed
a layer that begins the oxygen boom of the Triassic.
http://palaeo.gly.bris.ac.uk/Essays/wipeout/default.html
This, of course, is EXACTLY what I (for example)
would expect the record of the biggest impact of the
last half-billion years to look like. I don't think that
a half-million years is very long to recover from such
an immense whack! But the palaeontologists are saying
(in effect) that it can only be an asteroid disaster if
the dramatic aftermath of a major impact are limited
to the eye-blink of a fruit bat in time. In geologic terms,
they're demanding we find a discontinuity but no
after effects.
All these changes -- sulfate events, methane events,
dramatic climate change up, down and sideways, with
erratic atmospheric gas levels -- are perfectly explained
by an impact's effect on the Earth, particularly since
they're crammed into a short time span. The geologists
have a short time span event to blame: the flood basalts
of the Siberian Traps. Now, if they had the vaguest idea
what causes giant basalt floods, they'd be in a better
position to thumb their nose at an asteroid... But they
don't know.
We have flood basalt events all over the Solar
System, of course, and it's pretty obvious what
caused them. And we have a mechanism for flood
basalts on Earth having been caused by impacts
(focused shock waves). And the uncommonness
of flood basalts is on the same order as the
uncommonness of a Big Whack. Then, there are
the coincidences like Chicxulub and the Deccan
Traps, and this one, too.
In the Permian, there was only one continent,
good old Pangea, and lots of shallow ocean everywhere
else. Since the Permian event was a largely marine
extinction (94% of all marine species) and the odds on
an asteroid striking ocean are good, that too is suspicious.
Ocean crust is nowhere older than 200 million years,
so direct evidence (crater) of an ocean strike is gone.
Marenco's long-term sulfur isotope variations are
fully explicable in terms of the changes in continents
and oceans but are they great enough to wipeout
nearly all life?
For 5 million years after the Event, there is no
evidence of the existence of coral reefs. Note that
this not the absence of the coral animals that build
them, but the absence of the reefs themselves. OK,
I can believe that sulfite killed the coral critters, but
explain to me how it removed all their housing as
well? I have trouble with that. Of course, the biggest
tidal wave in a billion years could sweep away their
reefs, no problem... Corals came back, obviously,
but it took them 20-30 million years. Sounds like
they had to bulding all-new housing from scratch,
doesn't it? AND, the continental configuration that
supposedly caused all this difficulty hadn't changed
one bit in the intervening time! If the continental
configuration can cause a mass extinction, why
didn't it keep on causing it? Change of heart?
The half-million years of trouble marked by China's
Bed 25, 26, and 27 is only 30 cm thick and the layer
that shows the disaster (#25) is only 5 of those 30
centimeters, or about 80,000 years worth at uniform
rates of depositation. Of course, Bed 25 could be
from 10,000 years of depositation, too, or even only
1000 years.
All these timescales are too short to date at
251 million years in the past. Layer 25 is full of
evidence of the Siberian Traps vulcanism, and that
surely went on a while. So, the sharpness of
the triggering event is not determinable. And the
iridium layer, if there even was one, would be
lost in it, as would most extraterrestrial markers
('cept the gasses in the buckeyballs?).
I don't know if the Wilkes Land Crater will pan
out, nor Becker's Buckyballs, but if this were Las
Vegas, I would still put my money on the Permian
Whacker (knockout in the first round) over the
Siberian Gassy Wipeout as The Winnah!
Sterling K. Webb
--
- Original Message -
From: Ron Baalke [EMAIL PROTECTED]
To: Meteorite Mailing List meteorite-list@meteoritecentral.com
Sent: Friday, October 20, 2006 3:52
Re: Re: [meteorite-list] Chondrule formation mechanism
Thanks Darren - now this is more like it - h --- Darren Garrison [EMAIL PROTECTED] wrote: http://www.aspbooks.org/custom/publications/paper/index.phtml?paper_id=2447 Chondrule textures depend on the extent of melting of the chondrule precursor- material when cooling starts. Kind of begs the question - chodrules formed by collision, which causes melt - consider if one started from a steady molten state If viable nuclei I wonder what these viable nuclei are? viable cystal nuclei=Chondrules? remain in the melt, crystallization begins immediately, producing crystals with shapes that approach equilibrium. If not, crystallization does not occur until the melt is supersaturated, resulting in more rapid growth rates and the formation of skeletal or dendritic crystals. A chondrule texture thus indicates whether nuclei were destroyed, which implies a melting temperature above the liquidus temperature for its particular composition. The presence or absence of skeletal or dendritic crystals in chondrules can be used to constrain their peak temperatures, which range from 1400-1850°C. hmmm - collision temperatures of 1400-1850°C Heating times of less than a second result in aggregates of starting materials coated with glass, resembling agglutinates rather than objects with typical chondrule textures, suggesting that heating times are longer. different heating times=two mechanisms for chondrule formation? two classes 1)agglutinate 2)original? Chondrule textures can be duplicated with a very wide range of cooling rates, but if olivine zoning is to be matched the cooling rate should be within the range 10- 1000°C/hr. The size of overgrowths on relict grains cannot be used to infer cooling rates. Chondrules melted in a canonical nebular gas lose sulfur and alkalis in minutes, while iron loss from the silicate melt continues over many hours. Mass loss and isotopic fractionation can be suppressed if the partial pressures of the species of interest are high enough in the ambient gas. Chondrule bulk and mineral composition arrays can be reproduced to a large extent by evaporation. Yeah, but chondrules are found in matrices. However, condensation of SiO and how exactly is this SiO condensation supposed to occur? into the melt can simulate the zonation in some chondrules, with pyroxene and a silica polymorph near the rims. yeah, but could the silica rims have come from the inside? The partial equilibration of chondrule melt with noncanonical nebular gas would require heating for time periods of hours. Hm. Effervescence following a sudden release of pressure makes me think more of a can of Coke. :-) We all get our inspiration somewhere - __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Radar locates meteortite story in LA Times.
Where do I get my radar gun? http://www.latimes.com/technology/la-sci-meteorite21oct21,0,307156.story?coll=la-home-headlines _ Try Search Survival Kits: Fix up your home and better handle your cash with Live Search! http://imagine-windowslive.com/search/kits/default.aspx?kit=improvelocale=en-USsource=hmtagline __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chondrule formation mechanism
On Sat, 21 Oct 2006 16:41:48 -0700 (PDT), you wrote: Chondrule textures depend on the extent of melting of the chondrule precursor- material when cooling starts. Kind of begs the question - chodrules formed by collision, which causes melt - consider if one started from a steady molten state If viable nuclei I wonder what these viable nuclei are? viable cystal nuclei=Chondrules? How things appear to be (without trying to refer to chemical/minerological details that are beyond my level of knowledge) is that what became chondrules started out as fluff that slowly accumulated from the solar nebula, like you mentioned earlier. I imagine something like snowflakes, or dust-bunnies. Something fragile and irregular filled with empty spaces. Then, something (and there is no consensus on what that something was) heated those dust-bunnies/snowflakes up to the point where they melted-- and in a microgravity environment surface tension pulled them into little spheres. The viable nuclei means parts of that original fluff that didn't fully melt and became seeds for the new minerals to grow on. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Radar locates meteortite story in LA Times.
On Sat, 21 Oct 2006 17:56:51 -0600, you wrote: Where do I get my radar gun? Can the radar be tuned to find other types of stories in other publications? __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chondrule formation mechanism (Info Please)
Hi list What I have ben able to find personally on chondrule formation is rather sketchy. Even the otherwise comprehensive Encyclopedia of Meteorites by O. Richard Norton seems to skim over the mechanism in a paragraph. It's almost as if there is something which defies explanation and scientists abhor that more than nature abhors a vacuum. The slow cooling followed by a rapid quenching period is that which interests me most. I would dearly like to know where to find the most up-to-date theories on chondrul formation. I know about the R-R Lyrae heating, timescales and frequecies for newly forming stars. I need theory of protostellar nebula. Maybe Nebula density/stellar distance formula. The conditions in which and the timescale in which these 0.1- 3mm chondules formed. Contact off list if you wish. I need this information to assist me with a theory I have, the information for which comes from branches of science so diverse, that their relevance has not been realised. It is only by serendipity that I make the connection. My thoughts will appear here first (though I will ruthlessly hunt down and murder anyone who tries to plagarise my theory, hehe) Rob McCafferty --- Darren Garrison [EMAIL PROTECTED] wrote: On Sat, 21 Oct 2006 16:41:48 -0700 (PDT), you wrote: Chondrule textures depend on the extent of melting of the chondrule precursor- material when cooling starts. Kind of begs the question - chodrules formed by collision, which causes melt - consider if one started from a steady molten state If viable nuclei I wonder what these viable nuclei are? viable cystal nuclei=Chondrules? How things appear to be (without trying to refer to chemical/minerological details that are beyond my level of knowledge) is that what became chondrules started out as fluff that slowly accumulated from the solar nebula, like you mentioned earlier. I imagine something like snowflakes, or dust-bunnies. Something fragile and irregular filled with empty spaces. Then, something (and there is no consensus on what that something was) heated those dust-bunnies/snowflakes up to the point where they melted-- and in a microgravity environment surface tension pulled them into little spheres. The viable nuclei means parts of that original fluff that didn't fully melt and became seeds for the new minerals to grow on. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Henbury Auction Ending Today - AD
G'day, Just a reminder that there's a nice 220g Henbury individual ending today. Nice specimens around this size are extremely difficult to get in Australia now and this one is currently going for a fraction of its value! http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemih=002item=120042289479 Cheers, Jeff __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Rocks From Space Picture of the Day - October 22, 2006
http://www.spacerocksinc.com/October_22.html __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] Chondrule formation mechanism (Info Please)
jeez Bob, and all I was trying to do was to come up with a good excuse to personally examine that Krasnojarsk RSPOD Oct 15. You're just about ready to handle some of my asteroid and comet impact correspondence. Ed --- Rob McCafferty [EMAIL PROTECTED] wrote: Hi list What I have ben able to find personally on chondrule formation is rather sketchy. Even the otherwise comprehensive Encyclopedia of Meteorites by O. Richard Norton seems to skim over the mechanism in a paragraph. It's almost as if there is something which defies explanation and scientists abhor that more than nature abhors a vacuum. The slow cooling followed by a rapid quenching period is that which interests me most. I would dearly like to know where to find the most up-to-date theories on chondrul formation. I know about the R-R Lyrae heating, timescales and frequecies for newly forming stars. I need theory of protostellar nebula. Maybe Nebula density/stellar distance formula. The conditions in which and the timescale in which these 0.1- 3mm chondules formed. Contact off list if you wish. I need this information to assist me with a theory I have, the information for which comes from branches of science so diverse, that their relevance has not been realised. It is only by serendipity that I make the connection. My thoughts will appear here first (though I will ruthlessly hunt down and murder anyone who tries to plagarise my theory, hehe) Rob McCafferty --- Darren Garrison [EMAIL PROTECTED] wrote: On Sat, 21 Oct 2006 16:41:48 -0700 (PDT), you wrote: Chondrule textures depend on the extent of melting of the chondrule precursor- material when cooling starts. Kind of begs the question - chodrules formed by collision, which causes melt - consider if one started from a steady molten state If viable nuclei I wonder what these viable nuclei are? viable cystal nuclei=Chondrules? How things appear to be (without trying to refer to chemical/minerological details that are beyond my level of knowledge) is that what became chondrules started out as fluff that slowly accumulated from the solar nebula, like you mentioned earlier. I imagine something like snowflakes, or dust-bunnies. Something fragile and irregular filled with empty spaces. Then, something (and there is no consensus on what that something was) heated those dust-bunnies/snowflakes up to the point where they melted-- and in a microgravity environment surface tension pulled them into little spheres. The viable nuclei means parts of that original fluff that didn't fully melt and became seeds for the new minerals to grow on. __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Need Source For Bulk Tektites
Hi everyone, I am trying to obtain a source for bulk quantities of Tektites. Not too small, but not huge either. Perhaps the size of a US 25 cent piece at the very smallest, and at the most, up to the size of 3 US 25 cent pieces in a triangular configuration, or 4 of them side by side in a 2 x 2 matrix. I need them to be in good condition (not all bashed or chipped up from being tossed about in collecting buckets, or from being shipped all over the place.) And the price has to be really good (super cheap) too. Yeah - I know it sounds like I've been smoking funny cigarettes, but let me assure you, I have not. Well, at least I can't remember doing that...;-) Why do I need them? I am coordinating a fund raiser for my local astronomy club. I already have some nice unclassified NWA Meteorites, plus some nice, relatively inexpensive NWA 4293 that I am going to donate to the cause. So, OK - I have the Meteorites covered - but I want to add some Tektites to this as well. We figure that we can sell these at club events, and they can also be donated to school teachers without breaking the bank. We want to share education with respect to astronomy, meteorites, and basically any aspect of the hobby, and hopefully foster the growth of interest in astronomy in the community (kids, especially) and recruit some members. How much am I looking for? I would like to obtain a couple of kilos. I suppose shipping them can result in a little bit of chipping in transit, so that may be an unavoidable problem. If anyone can let me know where I can find a good, and inexpensive Tektite source, I would really appreciate hearing from you. Best regards, Ed Deckert __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] A probable iron meteorite fall in Italy many time ago
Hello Today my goldsmith have show to me 2 little rounded balls of iron with a grey dark crust well visible and some rust. He have say its of a person have take this 2 pieces many years ago after this is fall near the house of this person. The rust have the tipycal smell of the meteorites rust - its many different from the terrestrial rust - unfortunately the person not want cut one of the 2 pieces for seen if the cut face show the patterns why he want build this in a jewerly, but probably a nichel test its possible for seen if is a probable meteorite. Matteo M come Meteorite - Matteo Chinellato Via Triestina 126/A - 30173 - TESSERA, VENEZIA, ITALY Email: [EMAIL PROTECTED] Sale Site: http://www.mcomemeteorite.it Collection Site: http://www.mcomemeteorite.info MSN Messanger: spacerocks at hotmail.com EBAY.COM:http://members.ebay.com/aboutme/mcomemeteorite/ __ Do You Yahoo!? Poco spazio e tanto spam? Yahoo! Mail ti protegge dallo spam e ti da tanto spazio gratuito per i tuoi file e i messaggi http://mail.yahoo.it __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Brenham Project
This letter is my first post to the Meteorite List after being a long-time reader. I am the fortunate beneficiary of much recognition from so many of you related to my Brenham Project with Steve Arnold. Thank you for your kind words and encouragements. With this posting, I wanted to publicly recognize certain individuals who are the main contributors, in my opinion, to our most recent expedition and without whose efforts and creativity the wonderful story written by Associated Press would not have been possible. It was last July when I began conversations with Carolyn Sumners, Director of Astronomy of the Houston Museum of Natural Science. I offered HMNS an opportunity to join Steve and I in Kansas on a meteorite search and recovery project. Mrs. Sumners was excited about the opportunity and asked me what specifically HMNS could contribute as far as unanswered questions about the find. I told her we questioned the timing/age-date assigned to the fall and we wished to try to pin-down its timing. We discussed several methods for age-dating and left her and her experts to further discuss and implement the methods for age-dating. A second question is the direction of the meteorite fall, specifically, its bearing and descent angle. This question is more complex and we felt we needed to gather as much survey information as possible without disturbing the meteorites and the soil around them. At this point, Mrs. Sumners contacted Dr. Essam Heggy with the Lunar Planetary Institute regarding his ground penetrating radar work. I informed Steve and he said he would do his best for the museum. I remained convinced he could find another meteorite. After all details with the HMNS, LPI, and our landowners were worked out, I contacted our good friend, Darryl Pitt, to assist with all facets for release of information to the public regarding this expedition. You all know our results. Steve was able to pull the golden rabbit out of the hat. My sincere appreciation and congratulations to him once again and, if you have seen the strewnfield you understand why. He tells me he feels his ability to do so again from this point on will be less and less. Therefore, our search and recovery efforts for Brenham meteorites is beginning to wind-up. Carolyn Sumners group from HMNS included astronomers, geologists, paleontologists and archeologists with long and storied excavation and recovery experiences. It was a joy and a treat to be an observer of their efforts. I am excited for them and their unique meteorite recovery. Good going. Dr. Heggy, with LPI, was faced with a substantial change of conditions from those he originally anticipated in the field. Southwest Kansas had received quite a bit of rain and in the last three days, we were in constant heavy drizzle, blown sideways by 20-plus mile an hour winds. If not for the excitement of the project and all involved, it would have been miserable to be in such conditions for the 12 or more hours per day. Dr. Heggy adapted his equipment and techniques and continued to proceed as diligently as the rest of us without becoming discouraged. His efforts too were rewarded. Finally, but certainly not least, Darryl Pitt single-handedly prepared the initial press release and then he, along with the brilliant efforts of a colleague of his in New York, facilitated the amazing Associated Press story by Roxana Hegeman. Darryl worked closely with Roxana a day or two before Mondays final excavation of the museums 154-pound pallasite and she was very well prepared for what to expect on the final day. It was only yesterday evening I learned that Roxanas story has enjoyed the widest world-wide distribution of any story ever pertaining to meteorites (with the exception of the announcement of ALH84001). Certainly amazing. I am grateful to be a part of the Brenham Project. I have learned much more than I ever anticipated being a meteorite collector. This particular chapter of our project was such a treat to watch unfold. I am reminded of Gregs words to the List that this is an awesome story where meteorite hunters, collectors and scientists can join to work together closely in the field using new equipment to make a wonderful meteorite recovery. I am blessed to have participated. Congratulations to Carolyn Sumners and her HMNS team for their thoughtful work and the additional, continuing work to come both in age-dating the fall and hopefully determining the fall direction and angle. Great-going Dr. Heggy for your successful use and application of the GPR. Hats-off to Darryl for facilitating the AP wire story or, as I told him Tuesday morning when I learned it had already been picked up around the world Wow! Wow! Wow! Its amazing! To the List, so long for now. Steve and I are off to write another chapter for the Brenham Project and we intend to make it a good one. Very truly, Phil Mani Philip C.
[meteorite-list] Ad World's smallest pocket scale
Hi Everyone I have some wonderful scales for sale. I weighted a 241 gram meteorite on one and reweighed the same meteorite on an $1800.00 scale and it was accurate. That is incredible for something that can fit in your watch pocket. Check it out. http://www.meteorflash.com/SMALL.JPG Pocket Scales 1/10th Gram Key Chain Scale $20.00 each, Shipping is free in the US and $3.00 overseas. This is the worlds smallest pocket scale with slide cover. This compact scale is only 3 x 1.5 x 0.5; and is small enough to be used as a key chain. Although its tiny in size, it is fully functional with stainless steel platform and backlight. It can be used in many applications i.e. Weighing food products for calorie control for a personal diet program, for weighing precious stones or gems for the weekend rockhound enthusiast or any other hobby where 1/10th gram accuracy is needed. Product Features: High quality strain gauge load cell system makes it accurate in full capacity range. High density ABS housing and metal support makes it very durable. Stainless steel platform is safer for food and more durable than competitors units with plastic platforms. Detachable slide cover can be used as a scoop. High contrasts LCD display makes the readouts clear to read. TARE function covers units full capacity range. Attractive blue backlights make display easily readable in low light conditions. Specifications: Scale Size: 3" (D) x 1.5" (W) x 0.5" (H) Weighing Modes: g/oz/ct/gn Capacity: DW-250BK: 250g Accuracy: 0.1 gramPlatform Size:1.8" x 1.2"Platform Material: Stainless steel LCD Size: 1" x 0.3" Power:Two LR1130 lithium batteries (included)Packaging: 100 per caseColors Available:Black, Silver, White Regards Mike Martinez __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
Re: [meteorite-list] P-T Extinction: 'SickEarth' Book Recommendation
What a segway! Based on what I read there was evidence of a sick earth but Peter Ward's research showed a very rapid extinction of land animals. I just finished reading Gorgon: The Monsters That Ruled the Planet Before Dinosaurs and How They Died in the Greatest Catastrophe in Earth's History by Peter Ward. Ward spent decades studing the Permian Extinction in the Karoo district of South Africa. Ward was a specialist in the K-T extinction and looked kept an eye out for a similar impact component. The book is an account of the trials and tribulations of a geologist trying to do science, make a living, and raise a new family in the wilderness. The snobbbey and blood-letting amongst researchers is insightful to the way other researchers posion the pond in other fields. The science is pretty neat. The book is rarely predictible. Far too many dimentions to describe but the book is cheap online and a must read for anyone interested in the life of a geologist and novel solutions to solve obsticles. Ward's observations were that the land amimals that survived and flourished ultimately were the ones which had a bone structure that allowed for a flexible and greater lung capacity--side slung arms aka lizard-like. Research supported that there was a plunge in oxygen levels such that it was like moving from sea level to 12000ft. Part of the overall observation is that Gondwana moved over the south pole and in the ensuing ice age, sea level moved beyond the already meger contentinal shelves cutting shallow water habitat to nill killing the plankton bloom. The sea based food chain collapsed along with the oxygen production. There was a scarcity of land plants in the Permian besause so much of the land mass was at the interior of a massive water deprived landlocked soiless landscape. Life in the Triassic remained meger until the Breakup of Pangea opened up more shore line to the interior. The Siberian trapps at that time were above the Artic(North) not far from where they are today. For a book description: http://www.amazon.com/Gorgon-Paleontology-Obsession-Greatest-Catastrophe/dp/0670030945?tag2=gp04-20 Or Google Gorgon Ward Book. Regards, Elton __ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
RE: [meteorite-list] Brenham Project
And thank you for sharing it all with us Mr. Mani and Steve! Wonderful achievements! Sincerely, Moni From: Philip mani [EMAIL PROTECTED] To: Meteorite-list@meteoritecentral.com Subject: [meteorite-list] Brenham Project Date: Sat, 21 Oct 2006 09:13:47 -0500 This letter is my first post to the Meteorite List after being a long-time reader. I am the fortunate beneficiary of much recognition from so many of you related to my Brenham Project with Steve Arnold. Thank you for your kind words and encouragements. With this posting, I wanted to publicly recognize certain individuals who are the main contributors, in my opinion, to our most recent expedition and without whose efforts and creativity the wonderful story written by Associated Press would not have been possible. It was last July when I began conversations with Carolyn Sumners, Director of Astronomy of the Houston Museum of Natural Science. I offered HMNS an opportunity to join Steve and I in Kansas on a meteorite search and recovery project. Mrs. Sumners was excited about the opportunity and asked me what specifically HMNS could contribute as far as unanswered questions about the find. I told her we questioned the timing/age-date assigned to the fall and we wished to try to pin-down its timing. We discussed several methods for age-dating and left her and her experts to further discuss and implement the methods for age-dating. A second question is the direction of the meteorite fall, specifically, its bearing and descent angle. This question is more complex and we felt we needed to gather as much survey information as possible without disturbing the meteorites and the soil around them. At this point, Mrs. Sumners contacted Dr. Essam Heggy with the Lunar Planetary Institute regarding his ground penetrating radar work. I informed Steve and he said he would do his best for the museum. I remained convinced he could find another meteorite. After all details with the HMNS, LPI, and our landowners were worked out, I contacted our good friend, Darryl Pitt, to assist with all facets for release of information to the public regarding this expedition. You all know our results. Steve was able to pull the golden rabbit out of the hat. My sincere appreciation and congratulations to him once again and, if you have seen the strewnfield you understand why. He tells me he feels his ability to do so again from this point on will be less and less. Therefore, our search and recovery efforts for Brenham meteorites is beginning to wind-up. Carolyn Sumners' group from HMNS included astronomers, geologists, paleontologists and archeologists with long and storied excavation and recovery experiences. It was a joy and a treat to be an observer of their efforts. I am excited for them and their unique meteorite recovery. Good going. Dr. Heggy, with LPI, was faced with a substantial change of conditions from those he originally anticipated in the field. Southwest Kansas had received quite a bit of rain and in the last three days, we were in constant heavy drizzle, blown sideways by 20-plus mile an hour winds. If not for the excitement of the project and all involved, it would have been miserable to be in such conditions for the 12 or more hours per day. Dr. Heggy adapted his equipment and techniques and continued to proceed as diligently as the rest of us without becoming discouraged. His efforts too were rewarded. Finally, but certainly not least, Darryl Pitt single-handedly prepared the initial press release and then he, along with the brilliant efforts of a colleague of his in New York, facilitated the amazing Associated Press story by Roxana Hegeman. Darryl worked closely with Roxana a day or two before Monday's final excavation of the museum's 154-pound pallasite and she was very well prepared for what to expect on the final day. It was only yesterday evening I learned that Roxana's story has enjoyed the widest world-wide distribution of any story ever pertaining to meteorites (with the exception of the announcement of ALH84001). Certainly amazing. I am grateful to be a part of the Brenham Project. I have learned much more than I ever anticipated being a meteorite collector. This particular chapter of our project was such a treat to watch unfold. I am reminded of Greg's words to the List that this is an awesome story where meteorite hunters, collectors and scientists can join to work together closely in the field using new equipment to make a wonderful meteorite recovery. I am blessed to have participated. Congratulations to Carolyn Sumners and her HMNS team for their thoughtful work and the additional, continuing work to come both in age-dating the fall and hopefully determining the fall direction and angle. Great-going Dr. Heggy for your successful use and application of the GPR. Hats-off to Darryl for facilitating the AP wire story or, as I
